Looking back on three things discussed here before the St. Louis Rams’ preseason game Saturday night, a 20-19 defeat at Dallas:

1. Center of attention. Veteran Scott Wells, sidelined by knee surgery for much of the offseason, made his preseason debut after signing with the Rams in free agency. He called out line adjustments, pointing about the field as centers typically do.

Wells played Jay Ratliff to a stalemate on an early third-and-7 (left guard Quinn Ojinnaka gave up a sack on the play). The Cowboys’ Kenyon Coleman got past Wells with a quick first step, but Wells held on. Coleman did not disrupt the play.

Wells played a couple series and seemed to do fine. There were no botched center exchanges when he was in the game.

2. Offensive draft choices. Rookie running backs Isaiah Pead and Daryl Richardson got into the game early. Pead had a 47-yard kickoff return. He didn’t find much room to run while working with the first-team offense. Richardson fared better. The blocking for Richardson might have been better, but he also impressed with powerful strides. Richardson ran with determination through the play. He carried 10 times for 51 yards.

Pead bobbled a pass and couldn’t get away from defenders in the open field. But he did run hard in the red zone during a fourth-quarter drive ending with a touchdown pass from Kellen Clemens to Austin Pettis. Pead finished with nine carries for 22 yards.

The Rams did not get their young receivers involved early. Rookie second-round choice Brian Quick left the game in the second half after taking a crushing hit to the midsection, but he returned and contributed with a 39-yard reception. Fourth-round choice Chris Givens did not catch a pass.

3. Roster battles. Undrafted rookie safety Rodney McLeod seemed to improve his case for a roster spot, although evaluating secondary play can be tricky. McLeod made a positive first impression with an early tackle on special teams. He made a diving pass breakup on a risky third-down pass thrown over the middle in the fourth quarter.

At tight end, Mike Hoomanawanui made two receptions for 23 yards. One of his potential competitors for a roster spot, rookie Mike McNeill, threw the key downfield block on one of those receptions.

Clemens, the No. 2 quarterback, played deep into the fourth quarter. He completed 6 of 9 passes for 68 yards and the one score. Austin Davis finished up and led a quick touchdown drive, completing 4 of 5 passes for 53 yards. Davis showed pocket awareness. The offense perked up when he entered the game.